Little is known about the degree of disability, quality of life, and psychological well-being after major trauma. This prospective cohort study will determine the incidence and determinants of functional limitation after major trauma. Using the computerized San Diego County Regional Trauma System Registry (TREG) trauma patient data base (Appendix I), we propose to determine the incidence and predictors of functional limitation after major trauma in approximately 1200 men and women admitted prospectively to the University of California San Diego (UCSD) Trauma Center. Functional limitation after major trauma will be measured using the Quality of Well-being (QWB) scale at four time points; at discharge, and 6, 12, and 18 months after discharge. Multiple putative predictors of functional limitation after major trauma that will be determined include: (1) injury severity and body area(s) injured, (2) clinical course and treatment of the trauma, (3) sociodemographic characteristics, (4) social support and (5) post-injury psychological sequelae including depression and post-traumatic stress disorder. The prospective epidemiologic study will allow us to determine not only the incidence of functional limitation after major trauma but also the strength and independence of individual predictors of functional limitation. In addition we will be able to determine whether any combination(s) of patient attributes identifies those ag greatest risk so that these patients can be targeted for appropriate intervention. This information will help facilitate appropriate interventions for trauma patients dependent on their predictors of functional limitation.